Phonograph



J. T. LEITCH.

PHONOGRAPH.

APPLICATION FILED APR. 15, I92].

1 ,41 9 ,459 Patented June 13, 1922.

grvuc/wio'n (762m TLC lick om'reo sures PATENT omen-1 JAMES '1. LEITCH, OF ALLENTOWN, PENNSYLVANIA, ASSIGNOR OF ONE-FIFTH '10 TILGHMAN A. FREED AND ONE-FIFTH TO EVA S. FREED, BOTH OF ALLENTOWN,

PENNSYLVANIA.

PEONOGRAEH.

Specification of Letters 1; .ent. Patented J 11118 13 1922 Original application filed August 12, 1920, Serial No. 403,115. Divided and this application filed April To all whom it may concern:

Be it known that 1, JAMES T. LnrroH, a

citizen of the United States of America, re-

sidin at Allentown, in the county of Leigh and tate of Pennsylvania, have invented certain new and useful Improvements in Phonographs, of which the following is a specification.

This invention relates to .phonographs and other like sound reproducing devices.

More especially the invention relates to the amplifying sound box for phonographs.

One important object of the lnventlon is to provide an improved general construction of devices of this character.

A second important object of the invention is to provide an improved diaphragm for such sound boxes by the use of which the most sensitive sounds will be properly re produced and the sensitive overtone waves properly blended so as to avoid harshness and the so called blastingl A third important object of the inventlon is the-provision of a sound box havinga resonator of novel construction whereby increased amplitude of vibration of the sound waves will be obtained and the absorption and consequent waste of sound producing vibrations be eliminated.

A fourth important object of the invention is to provide an improved arrangement of needle arm and its bracket or support therefor' in order to prevent damping of vibrabox as well as to eliminate the production of metallic efl'ects.

A fift lrimportantobj'eet of the invention is the provision of a novel amplifier so connected with the resonator that the produced vibrations will be collectedland amplified. With the above and other objects in view, the invention consists in general of certain novel details of construction and combinations of parts hereinafter fully described,

' several views, and

'ig.'1 is. aface view of an amplifier coni powdered with ,metal.

Serial No. 461,615.

structed in acordance with this invention and showing its position relative to an ordinary sound box.

Fig. 2 is a detail section on the line IIII.

Fig. ,3 is a perspective of part of a diaphragm.

In the drawing there is shown a sound box and amplifier particularly adapted for use in connection with the device shown in my mica copending application filed August 12, 1920, and bearing the Serial No. 4( )3 ,115 of which this application is a div1s1on. v v

'The sound box shown in the copending application is illustrated in general, in the present case, at 10. The bracket and con necting means also referred to in the abovementioned application tively at 11 and 12.

The amplifier includes a casing 13 having are shown respeca beaded edge 14 wherein are rubber rings 15 sition by an angle ring 19 fitted within the casing 13. Thus the amplifier forms a closed box the ends of which are constituted by mica diaphragms. It will be noted that the connector 12 is fixed to the diaphragm 16 as indicating at 20.

It is obvious that the case 12 is merely typical of a suitable means for vibrating the diaphragm 16.

I preferably make one or both of these diaphragms 16 and 18 of peculiar character, the diaphragm thus constructed, being formed from a thin sheet of mica having its surface covered by a multitude of fine particles of metal 21, the latter being held on the mica by some suitable adhesive so that the surface of the diaphragm appears as though The effect of this metallized mica diaphragm is to render the reproducer responsive to weak and sensitive sounds while at the same time the overtone waves are properly blended. Thus the ireproduction has all of the characteristics of the original sound without any harshness or blasting being caused by improper or defective vibrations to the dmghragm.

There has thus been rovi ed a simple and efficient device of the kind described and for the purpose specified.

It is obvious that minor changes may be made in the form and construction of the invention without departing from the material principles thereof. It is not therefore desired to confine the invention to the exact form herein shown and described, but it is JAMES T. LEITCH. 

